Headlamp reflectors

[Malcolm Parker]

I would have thought that a deeper dished reflector would give a more concentrated beam.  If the headlamp glass is of uniform thickness, ie is not acting as a lens, then its actual shape should not materially affect the beam of light. It is all about focusing the source of light.   As I understand things, an LED light source is only bright when you look directly at it, so there cannot be much light going back or sideways onto the reflector?   This is probably why LEDs look bright to oncoming traffic but project very little light.